A burnt taste with a new coil is often caused by not priming the coil properly before use. When the coil's cotton isn't fully saturated with e-liquid, it can burn as soon as you fire your device—resulting in that harsh, burnt flavor. To avoid this, always prime your coil by applying a few drops of vape juice directly onto the cotton and letting the tank sit for 5–10 minutes before vaping.
Using your vape at too high of a wattage or chain vaping can also cause premature coil burning. Always follow the recommended wattage range and give your coil time to re-saturate between hits for the best flavor and coil life.